Electrical apparatus



O. E. MARVEL Filed March 2I 1925 June 24, 1930.

ELECTRICAL APPARATUS Patented June 24, 1930 'illiti'l STATES i'lfltpll OFFEC ORIN E. MARVEL, OF DAYTON, OHIO, ASSG-NOR, BY MESNE ASSIGNMENTS, TO GENERAL MOTORS RADO CORPORATION, OE' DAYTON, OHIO, A CORPORATEON OF OHIO ELECTRICAL .AFPARATUS Application led March 2, 1925. Serial No. 12,780.

This invention relates to apparatus for receiving radio signals and particularly to circuit arrangements for ppviding a satisfactory local source of energy therefor.

@ne of the principal objects of the invention is to provide an apparatus for receiving radio signals in which the switch for the lament circuit is arranged to also control related circuits.

Another object of the invention is to provid-e an apparatus for receiving radio signals having means for automatically connecting the storage battery with a battery charger upon the opening of the lament circuit.

Further objects and advantages of the present invention will be apparent from the following description taken in connection with the accompanying drawings, in which- Fig. l is a schematic diagram of the present invention;

Figs. 2 and 3 show several operating positions of the iilament control switch of Fig. l; and

Fig. 4 is a modified form of the invention.

Apparatus for receiving radio signals, as now known, requires for its successful operation a local source of current which may be a storage battery. Owing to the frequent and extensive operation of such apparatus it often happens that the Vbattery reaches a condition approaching full discharge without the operator being aware oi' this condition, and as a consequence of such a condition of the battery the operation of the receiving apparatus is likely to be affected uniiavorably. For the best operation of radio receiving apparatus as well as to secure the longest life and greatest reliability from the storage batteries, it is highly desirable that the batteries be continually maintained at full charge. The present invention provides means for accomplishing this result by automatically connecting the storage battery with a battery charger or source of current immediately upon discontinuing the use of the receiving apparatus for the reception of signals.

Referring to the drawings, denotes the panel of a radio receiving apparatus or set and 21 the storage battery or local source of electrical energy for the radio receiving apparatus. rlhe receiving apparatus includes local work circuits such for example as the filament circuit herein illustrated in which the iilament of an electron discharge device 22 is connected to the battery 2l by means of the wires 23 and 24. For controlling the iilament or work circuit 23, 24 the receiving apparatus is proviced with a switch 25 which may be of push-pull or other usual type, the construction ot the switch herein illustrated being such that when the switch 25 is pulled outwardly from the panel the work circuit 23, 24- is closed and the switch is then in what may be termed its closed position, as illustrated in Fig. 2. lWhen the switch is pushed inwardly to its open position the work circuit 23, 24E is open as illustrated in Fig. l.

Associated with the radio receiving apparatus is a second source of electrical energy adapted to charge the storage battery 2l, this second source of electrical energy being herein illustrated as a battery charger 26 having a primary winding 27 connected with line circuit or wires 28 and a secondary winding 29 having its secondary or output circuit connected with the terminals of battery 2l by means of wires 30 and 3l. rlhe primary or input circuit o'i the battery charger is provided with a switch 32 having spring switch blades 33 and by which the primary circuit may be opened or closed to control the operation ot the battery charger. The battery charger herein illustrated is one oi the vibrating-armature type having an armature 35 which is adapted to vibrate between cooperating contacts 36 and 37. In this type of battery charger the vibrating armature 35 may come to rest against one i oi" the contacts 36, 37 when the batteryk charger4 is not in use thereby maintaining the secondary circuit closed across the terminals of the battery and causing a discharge of the battery through the secondary circuit. To guard against this contingency the secondary circuit is also provided with a switch 38 having cooperating spring switch blades 39 and 40 to open or close the secondary circuit simultaneously with the opening or closing of the primary circuit. It will be understood that the present invention is not limited to the use of the particular type of battery charger herein illustrated but that any other type of battery charger may be employed and that in such other type of battery charger as well as in the type herein shown the secondary switch 38 may be omitted if desired.

The Work circuit 23, 24C including the filament 22 has been taken as illustrative of one or all of the work circuits of the radio receiving apparatus which are normally dosed during the operation of. the radio receiving apparatus, and which circuits are open or in a non-flow conditionwhen the radio receiving apparatus is not in use. The present invention (contemplates the connection of the battery charger 2G or second source of electrical energy to the battery 21 as soon as the use of the radio receivingr apparatus is discontinued, and it provides suitable means for automatically accomplishing this connection, which means will now be described.

The means for automatically connecting the battery charger 26 in charging relation with the battery 21 when the filament or Work circuit is opened consists of an electromagnet 50 having a pivoted armature 51 which is adapted to be controlled thereby to open or close the switches 32 and 38 of the battery charger circuits. The e'lectromagnet has a suitable winding 52 which may be connected in an energizing circuit which extends from one side of the battery through wire 53, contact 54 carried by the filament control switch, wire winding 52 and wire 56 to the other side of the battery. The winding 52 may also form part of a holding circuit which extends from one side of the battery through wire 53, contact 54 carried by the filament control switch 25, wirc 57, armature 58, wire 59, Winding 52, and wire 56 to the other side of the battery.

The construction and arrangement of the filament control switch 25 and the contacts cooperating therewith is such that while the filament or Work circuit 23, 24 is closed the energizing and the holding circuits of the eiectromagnet 50 are open as illustrated in Fig. 2. This is the normal condition for operation of the radio receiving set and it W-'iill be observed, the electromagnet 50 being dleenergi-zed, that the switches 32 and 38 ot the ybattery charger are open, and the battory charger 26 is therefore disconnected from the battery 20.

When it is desired to discontinue operation o'f the radio receiving set the filament control switch 25 is moved from its closed position, illustrated in Fig. 2, to its open position illustrated in Fig'. 1. This movement is normally fairly rapid, but in moving from thc closed position shown in Fig. 2 to thc open position shown in Fig. 1, the filament control switch passes through the intermediate position illustrated in Fig. 3. In this position it will be observed that the filament circuit is already open but the contact ring 54 has connected the wires and to close the energizing circuit thereby causing the electromagnet 50 to attract the arrnxturcs 5l and 58. Attraction of the armature 51 closes the switches 3 2 and 38 to connect the battery charger 26 in operative charging relation with the battery 21. Attraction of the armature 58 closes the holding circuit, which, as heretofore stated, includes the wire 57 and armature 58. On further movement of the filament control switch from the position shown in Fig. 3 towards that .shown in Fig. 1 the contact ring 54 closes the holding circuit from wire 53 to wire 57 so that now current is flowing through both thi` energizing circuit and the holding circuit. The final movement of the filamenti control switch 25 to the position shown in Fig. 1 serves to open the energizing circuit between wires 53 and 55 so that the electromagnet is energized solely by virtue of the current flowing through the holding circuit which includes the switch 58.

The battery charger 26 being thus connected to the battery 21, the latter is charged and such charging continues until the battery has attained a condition of full charge. It is Well known that after a battery is fully charged, any further charging thereof will cause liberation of gas therefrom, a condition Which is commonly termed gassing of the battery. In the present invention advantage is taken of this phenomenon to disconnect the battery charger from the battery when the latter has attained itsl full charge. A funnel or other suitable conduit 60 is connected with the interior of one or more of the battery cells, and the upper end of the funnel is closed by means of a suitable ilexible wall 61 to form a gas chamber, the flexible wall 61 being herein illustrated as a rubber diaphragm. A switch 62 having spring switch blades 63 and. G4 is connected in the wire 56 of the electromagnet control circuits. The switch 62 is normally closed but when the battery gases as a result of the battery having attained its full charge the switch G2 is opened thereby breaking the holding circuit to deenergizc the winding 52 of the electromagnet. Such deencrgization of the electromagnet releases the armature 58 to open the holding circuit. and also releases the armature 51 to open the switches 32 and 38 of the battery charger 2G, thereby rcnlill) dering the latter inoperative to further charge the battery.

Should it be desired to resume operation of the radio receiving apparatus before the battery is fully charged and before the switch 62 has operated, it will be seen that the mere usual movement of the filament control switch to the normal position for closing the iilament circuit, as illustrated in Fig. 2, will open the circuits of the electromagnet to deenergize the latter and automatically discontinue operation of the battery charger 26.

While the arrangement illustrated in Fig. l shows one means responsive to the state of charge of the battery for discontinuing the charging operation when the battery attains full charge, it is to be understood that any other suitable means may be employed for accomplishing this result. One such alternative means is illustrated in Fig. 4. Advantage is taken of the fact that the voltage across the terminals of the battery being charged increases as the charging progresses so that when the battery attains full charge the voltage has attained a certain value which depends somewhat upon the rate of charge but which may nevertheless be taken as corresponding to and indicating a full charge of the battery. The general arrangement of circuits and parts in Fig. 4 is the same as shown in Fig. l except that instead of the chamber 60 for receiving the battery gases, there is connected between the wires 56 and 59 a thermostat heating circuit 69 including the thermostat heating coil 7 O'which latter surrounds or is in heating relation with a bi-metallic thermostat blade 7l.

A second or reverse winding 72 is placed upon the electromagnet 50 this winding also being connected between the wires 56 and 59. The circuit of this reverse winding 72 is adapted to be controlled by the thermostat blade 71 which, when it is heated sufiiciently, moves into engagement with the contact 73 to close the circuit through the reverse winding 72. At other times, when the thermostat blade 71 is not heated sufficiently, then the circuit through the reverse winding is open and the reverse winding is therefore ineffective.

1n the operation of this form of the invention it will be seen that when the switch 25 is moved to position to open the filament circuit and to close the charging circuit, the thermostat heating circuit 69 is immediately connected across the terminals of the battery. Current thus flows through the thermostat heating coil 70 to heat the thermostat blade 7l, but the heat generated by the heating coil 7 O is not suliicient to cause the thermostat blade 71 to engage the contact 7 3 because of the low voltage of the battery. As the battery becomescharged the voltage thereof rises and thisresults in an increased current How in the thermostat heating circuit until finally at a predetermined voltage corresponding to full charge of the battery, the thermostat blade 7l is caused to engage contact 73 thereby closing the circuit of the reverse winding 72. The reverse winding 72 is so arranged that upon the flow of current therethrough its effect opposes that of the main winding 52 to deenergize the electromagnet 50 thereby permitting the holding circuit to open at 58, and to discontinue the charging operation. The thermostat blade may be adjusted to operate at any desired voltage by means of the adjusting screw 74. While it has been stated that the reverse winding 72 operates to deenergize the electromagnet 50, it should be understood that it is not essential to the successful operation of this form of control that the electromagnet be entirely deenergized, but only that the eifective ampere turns thereof be reduced to such a point as to permit the armature 58 to drop out. 1t will be understood that the change in the number of ampere turns in the electromagnet 50 may be readily effected by causing the thermostat 7l to close a circuit of suitable resistance which is in shunt with the winding 52, whether this shunt circuit is exterior to the electromagnet 50 or whether it includes a reverse Winding for the electromagnet as herein illustrated.

From the foregoing it will be apparent that the present invention provides a radio receiving apparatus having means for at all times and automatically maintaining the battery in a fully charged condition. Further, it provides such an organization and arrangement of parts that the battery charging may be eiiected automatically merely by the normal and usual movement of the control switch with which the radio receiving apparatus is already provided for starting or stopping operation of the radio receiving apparatus.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope'of the invention which is defined in the appended claims.

lVhat is claimed is:

l. An apparatus for receiving radio signals comprising, in combination, a radio re- .ceiving set having a iilament circuit, a

control panel for said set, a manually operable switch carried by said control panel for opening and closing said circuit, a source of electrical energy connected with said circuit, a second source of electrical energy adapted to charge said iirst source of energy, and means operable upon the opening of said lament circuit by the opening movement of said switch to automatically connect the second source of energy in charging relation with said first source, and means responsive to the state of charge of said first source to disconnect the second source therefrom.

2. An apparatus for receiving radio signals comprising, in combination, a radio receiving set having a work circuit, a switch carried by said receiving set and included in said Work circuit for opening and closing said work circuit, a source ot electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and means operable upon the opening o? said switch to automatically connect the second source ot energy in charging relation with said first source.

3. An apparatus for receiving radio signals comprising, in combination, a radio receiving set having a filament circuit, a control panel for said set, a manually-operable control switch associated with said panel for openin and closing said filament circuit, a source o electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and relay means operable upon the opening of said switch to automatically conneet the second source of energy in charging relation with said first source.

4. In an apparatus for receiving radio signals having a work circuit and a switch therein for opening and closing said circuit, a source of electrical energy connected with said circuit, a second source of electrical energy com rising primary and secondary circuits, adiipted to charge said first source of energy, and means operable upon the opening of said work circuit by said switch to connect the second source of energy in charging relation with said first source, said means comprising an electroma et connected with one oia said sources an adapted to be energized thereby, an amature controlled by the electromagnet, and switch means conected in the primary and secondary circuits of said second source to control the operation thereof.

5. In an apparatus for receiving radio signals having a work circuit and a switch therein for opening and closing said circuit, a source of electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and means operable upon the opening of said work circuit by said switch to connect the second source of energy in charging relation with said first source, said means comprising an electroma et, armature and switch means controiid by said electromagnet, an energizing circuit for the electromagnet, and a holding circuit for the electromagnet.

6. In an apparatus for receiving radio signals having a work circuit and a switch therein adapted to be moved between opening and closing positions to open or close said work circuit, a source of electrical energy connected with said circuit, a second source of electrial energy adapted to charge said first source of energy, and means operable upon the movement of said switch towards open position for opening said work circuit to connect the second source of energy in charging relation with said first source, said means comprising an electromagnet having energizing and holdingr circuits, said switch being constructed and arranged to close the energizing and holding circuits upon movement towards opening position, and then to open the energizing circuit upon further movement towards openin position.

In an apparatus for receiving radio signals having a work circuit and a switch therein adapted to be moved between opening and closing position to open or close said work circuit, a source of electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and means operable upon the movement of said switch towards open position for opening said Work circuit to connect the second source of energy in charging relation with said first source, said means comprising an electromagnct having energizing and holding circuits, said switch being constructed and arranged to close the energizing circuit upon movement towards opening position, to also close the holding circuit upon further movement towards opening position, and then to open the energizing circuit upon still further movement towards opening position.

8. An apparatus for receiving radio signals comprising, in combination, a radio receiving set and a work circuit, a switch carried by said receiving set and included in said work circuit for opening and closing said circuit, a source of electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and means operable upon the opening of said work circuit by said switch to connect the second source of energy in charging relation with said first source, said means comprising an electromagnet connected with one of said sources, switch means controlled by the electromagnet for controlling said connection of said second source with said first source, and means responsive to the state of charge of said first source of energy to change the magnetic effect of said electromagnet whereby to cause operation of said switch means to interrupt the charging operation.

9. In an apparatus for receiving radio signals having a work circuit and a switch therein for opening and closing said circuit, a source of electrical energy connected with said circuit, a second source of electrical energy adapted to charge said first source of energy, and means operable upon the opening of said Work circuit by said switch to connect the second source of energy in charging relation With said rst source, said means comprising an electromagnet having a winding connected with one of said sources7 switch means controlled by the electromagnet for controlling said connection of said second source with said first source, and means including a second Winding on the electromagnet responsive to the state of charge of said iirst source of energy to change the effective ampere turns of said rst Winding whereby to cause operation of the switch means to interrupt the charging operation.

In testimony whereof I hereto aHX my signature.

ORIN E. MARVEL. 

